时效析出强化型铜合金是弹性器件、密封件、引线框架、导体等关键部件的重要材料，但强度一般低于1000MPa，且强化同时塑性会急剧降低，严重影响其使用性能。其根本原因是对析出相特性与位错钉扎作用及其通过析出时的运动行为之间的相互关系认识不足，而且目前的强化模型还无法准确描述复杂析出相转变过程中的强化行为。申请者发现Cu-Ni-Mn合金中低错配度的纳米有序相的组合可发生切过/绕过强化机制的转及叠加，产生位错切过后的滑移变化，具有极为优异的强度/塑性组合。本项目拟研究Cu-Ni-Mn合金低错配度有序析出相与强化/塑性机制之间的定量关系，析出相强化临界条件判据函数，建立时效全过程的强度理论模型，以突破时效强化型铜合金的性能瓶颈。本项目能够突破Cu-Ni-Mn合金的强韧化合金相设计控制技术，提高强韧性能，突破其力学性能极限。在强度理论模型的指导下优化其形变时效制备工艺技术，实现其在重要工业领域的应用。

The precipitation hardening copper alloys are widely used as key components such as elastic devices，seal components， lead frame and conducts etc. The applications of these alloys are seriously affected by the strength which is generally below 1000MPa and the rapid reduction of plastics during the strengthening process. The fundamental cause of the limitations on improvement of mechanical properties of these alloys is the lack of understanding of the relationship between the characteristics and the pinning behavior and movement of dislocations when travelling through the precipitates. Meanwhile, the current theoretical model of precipitation strengthening can not be used for the accurate description of the strengthening effects caused a series of complicated phase transformations. It has been found recently by the applicants that the occurrence of the transformation and accumulation of the hardening mechanisms of nano- scaled ordering precipitations with fairly low mismatch, i.e., dislocation by-cutting and by-passing mechanisms, as well as the transformation of dislocation slip systems, are possible in Cu-Ni-Mn alloy, leading to the excellent combination of both strength and plastics. Therefore, the quantitative relationship between these low- mismatched ordering precipitations and mechanism of strengthening and plastics will be studied in this project. The criterion function of different precipitation strengthening mechanisms will be developed, and a new theoretical model of strengthening corresponding to the entire aging process will be established, in order to break through the limitations of the mechanical properties. The designing and controlling technology of ordering precipitation of Cu-Ni-Mn alloy will be developed to improve the strength and plastics. The preparation technology, i.e., deformation and aging process, can be optimized under the guidance of the newly developed theoretical model of strengthening, in order to realize the applications of this alloy on key industrial areas.